Linear Algebra and the C Language/a0c6

Install and compile this file in your working directory.

/* ------------------------------------ */
/*  Save as :  c00c.c                   */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
#define   RCA        RC5
/* ------------------------------------ */
/* ------------------------------------ */
double f(
double x)
{  
        return(sin(2*x));
}
char  feq[] =  "sin(2*x)";
/* ------------------------------------ */
double g(
double x)
{  
        return(2*sin(x)*cos(x));
}
char  geq[] =  "2*sin(x)*cos(x)";
/* ------------------------------------ */
/* ------------------------------------ */
void fun(void)
{
double **A             = rsymmetric_mR(i_mR(RCA,RCA),999.);
double **sin2_A        =               i_mR(RCA,RCA);
double **sincos_A      =               i_mR(RCA,RCA);

double **EigsVector    =               i_mR(RCA,RCA);
double **T_EigsVector  =               i_mR(RCA,RCA);

double **EigsValue     =               i_mR(RCA,RCA);
double **sin2_EigsValue   =            i_mR(RCA,RCA);
double **sincos_EigsValue =            i_mR(RCA,RCA);

double **T1            =               i_mR(RCA,RCA);
  
  clrscrn();
  printf(" A :");
  p_mR(A,S10,P4,C6); 

  eigs_V_mR(A,EigsVector); 
  transpose_mR(EigsVector,T_EigsVector);
      
/* EigsValue : T_EigsVector * A * EigsVector */
  mul_mR(T_EigsVector,A,T1);
  mul_mR(T1,EigsVector,EigsValue);     
  
  printf(" sin(2*A)");
  f_eigs_mR(f,EigsValue,sin2_EigsValue); 
     mul_mR(EigsVector,sin2_EigsValue,T1);
     mul_mR(T1,T_EigsVector,sin2_A); 
       p_mR(sin2_A,S10,P4,C6); 

  printf(" 2*sin(A)*cos(A)");
  f_eigs_mR(g,EigsValue,sincos_EigsValue);
     mul_mR(EigsVector,sincos_EigsValue,T1);
     mul_mR(T1,T_EigsVector,sincos_A);
       p_mR(sincos_A,S10,P4,C6); 
            
  f_mR(A);
  f_mR(sin2_A);
  f_mR(sincos_A);
    
  f_mR(EigsVector);
  f_mR(T_EigsVector);
  
  f_mR(EigsValue);
  f_mR(sincos_EigsValue);    
  f_mR(sin2_EigsValue);    
      
  f_mR(T1);
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));

do
{
  fun();

} while(stop_w());

  return 0;
}
/* ------------------------------------ */
/* ------------------------------------ */

Screen output example:

                                                                                       
 A :
 -136.0000  +554.0000  -594.0000  +199.0000  -911.0000 
 +554.0000    +2.0000   -70.0000  +231.0000  -932.0000 
 -594.0000   -70.0000  +701.0000  -227.0000  +675.0000 
 +199.0000  +231.0000  -227.0000   +56.0000  +926.0000 
 -911.0000  -932.0000  +675.0000  +926.0000  +662.0000 

 sin(2*A)
   -0.7572    +0.1712    +0.0369    +0.3567    +0.1338 
   +0.1712    -0.2770    +0.5685    +0.4319    +0.0390 
   +0.0369    +0.5685    +0.1165    -0.2389    -0.3071 
   +0.3567    +0.4319    -0.2389    +0.0555    +0.3505 
   +0.1338    +0.0390    -0.3071    +0.3505    -0.7886 

 2*sin(A)*cos(A)
   -0.7572    +0.1712    +0.0369    +0.3567    +0.1338 
   +0.1712    -0.2770    +0.5685    +0.4319    +0.0390 
   +0.0369    +0.5685    +0.1165    -0.2389    -0.3071 
   +0.3567    +0.4319    -0.2389    +0.0555    +0.3505 
   +0.1338    +0.0390    -0.3071    +0.3505    -0.7886 


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